Various devices in a wide variety of applications are used to selectively dispense a metered amount of a fluid. For example, an inkjet printer is a printing machine in which a printhead assembly is commonly mounted on a moveable printing carriage. As the carriage moves with respect to a print medium, such as paper, the printhead assembly selectively dispenses droplets of liquid ink onto the print medium to form a desired image. The printhead can be incorporated into a replaceable cartridge that can be coupled to the moveable carriage when installed.
There are multiple configuration possibilities for such inkjet printing systems, including on-axis and off-axis configurations. In the on-axis configuration, a cartridge having a printhead is mounted on the moveable carriage, or a replaceable ink supply cartridge mounts to the printhead. The cartridge contains an internal ink reservoir, and the entire cartridge is replaced when this internal ink reservoir is exhausted.
The off-axis configuration features an ink reservoir mounted off the printhead. The off-axis ink reservoir intermittently or continuously supplies ink through a conduit, typically a flexible ink conveying tube, to the inkjet printer's printhead.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.